Short answers, pulled from the story.
Apollonius of Rhodes was an ancient Greek author who flourished in the first half of the 3rd century BC. He is best known for the Argonautica, an epic poem about Jason, Medea, and the quest for the Golden Fleece. He served as a scholar and librarian at the Library of Alexandria and is believed to have headed that institution before being succeeded by Eratosthenes.
The Argonautica tells the story of Jason and the Argonauts and their quest for the Golden Fleece. The poem spans four books and fewer than 6,000 lines. It is notable for its human, non-heroic portrayal of Jason, its treatment of the love between Medea and Jason in book three, and its integration of mythical and geographical knowledge.
The evidence for a feud between Apollonius of Rhodes and Callimachus is thin and contested. An epigram in the Palatine Anthology mocks Callimachus, and his poem Ibis was described as targeting Apollonius, but both Lives of Apollonius stress the poets' friendship and say they were buried together. Most modern scholars now consider the feud to have been greatly sensationalised, if it occurred at all.
Multiple ancient sources, including the 2nd-century BC papyrus P.Oxy. 1241, confirm that Apollonius held the position of head of the Library of Alexandria. P.Oxy. 1241 records that he was succeeded by Eratosthenes, a succession that must have occurred after 247/246 BC when Ptolemy III Euergetes came to power.
The epithet 'Rhodian' attached to Apollonius because ancient sources record he moved to Rhodes from Alexandria, but scholars are uncertain whether he was born there or even spent significant time there. Some modern scholars suggest the epithet may simply reflect the fact that he wrote a poem about Rhodes rather than any physical connection to the island.
Apollonius wrote a series of foundation poems, known as ktiseis, dealing with the mythical origins of cities. These included poems on Alexandria, Cnidus, Naucratis, Rhodes, Caunus, and Lesbos. Only fragments survive, the longest being twenty-one hexameters from the Founding of Lesbos, quoted by the author Parthenius.